The United States, South Korea and Japan have remained firm on the condition of denuclearization as the basis for credible talks.

Those expectations have been destroyed on several occasions.

North Korea conducted its sixth nuclear test on Sept. 3, launched what experts say are two intercontinental ballistic missiles in July, the Hwasong-14, then launched two midrange rockets, the Hwasong-12, on Aug. 29 and on Sept. 15.

Ri, who will meet with Guterres, could also meet briefly with South Korean Foreign Minister Kang Kyung-hwa.

The two spoke for about three minutes at the ASEAN Regional Forum in the Philippines in August.

U.S. President Donald Trump on Tuesday described the Kim Jong Un regime as "deprived," during his address to the U.N. He condemned the human rights situation in North Korea.

"Denuclearization is its only acceptable future," Trump said, after denouncing the death of "innocent American college student" Otto Warmbier and the assassination of Kim Jong Nam, the older half-brother of the North Korean leader.